In certain cases, it is necessary to detect the temperature of a person, in particular changes of temperature. For example, a bedridden person having a fever should be watched in order to take actions if the temperature of the person becomes too high, i.e. exceeds a certain threshold value. For example, anxious parents feel the need to “take the temperature” frequently on their ill small children when having a fever, to find out how the illness develops. In reverse, it is desirable to monitor whether the temperature of a person suffering from hypothermia falls below a certain threshold value. Further, it may be of interest to detect and analyse the variations in temperature of a person during a period of time. For example, such information may be used to make a diagnosis of a patient, or estimate the sleep quality or general state of a person, whether he/she is ill or well.
Temperature monitoring is typically performed by applying one or more thermometers, or temperature sensors generally, at the person in question, typically using a wired connection to some separate registering unit, for automatic registration and possibly processing and analysis of measurement values from the thermometer. Of course, such a solution will result in some degree of inconvenience to the person carrying such a thermometer at or inside the body, as well as the risk that the thermometer comes off or for some reason does not work properly. Alternatively, the temperature is manually measured at frequent instances, which is labour-intensive, however, in particular when the person must be monitored continuously. Thus, it is a problem to be able to register the temperature of a person, using a minimum of labour, in a reliable way and without bothering the person.
Another area of interest is the comfort for lying or sitting persons. For example, it is a problem to maintain just the right temperature which is comfortable for a person lying in a bed or the like. Lying injuries or bedsores may also occur on persons who for some reason remain bedridden and relatively motionless during long periods of time due to, e.g., physical injury, disease, disablement or high age. Further, it may generally be uncomfortable to lie or sit down for long periods, particularly in the same position, often resulting in stiffness and numbness. Hence, there is a need to be able to control the temperature and also further characteristics in a bed or seat where a person is present, in order to provide a high convenience and to avoid discomfort and injuries.